The attack in the wee small hours on the US government cultural centre in Calcutta has raised the temperature of war again in the subcontinent. Indian security officials have been blaming a Paksitan-based pan-Islamic group called Harkat-e-Jihadi Islami (Heji).

Although the Indian home minister added another dimension to the incident when he blamed a Dubai-based man working for an Indian underworld crime boss, Dawood Ibrahim, allegedly linked with Pakistan's intelligence services, the attack seems to be yet another attempt to provoke an Indo-Pakistani war and thus to derail Musharraf's mission to rid Pakistan of pro-Taliban jihadi elements.

Who are Heji? Calling themselves the "Army of the Allah", the Heji and Taliban militia have their roots in Jamiat-e-Ulemai Islam Pakistan, who have been vehemently opposing Musharraf's U-turn on Pakistan's Afghan policy.

Heji first came under the spotlight in Kashmir when it banned the Hindu pilgrimage Amarnath Yatra in 1993 in retaliation to the demolition of the Babri Masjid mosque. Heji demanded the reconstruction of the mosque and wanted other closed mosques to be reopened.

The group again made news when it kidnapped two Britons from Aroo, Pahalgam on June 6 1994 and was also suspected to be involved in the abduction of five western tourists in July 1995, allegedly by masquerading as the non-existent Al-Faran group. The two Britons were released unhurt after the intervention of the Mirwaiz (religious leader) of south Kashmir, the late Qazi Nisar.

However, Heji denied any role in the latter abduction. Of these western tourists, one escaped, a Norwegian national was beheaded, while the police claimed that DNA tests had confirmed that a body exhumed in south Kashmir in 1997 was that of Paul Wells, also among the tourists abducted. The fate of the other two remains unknown.

Heji was launched in 1980 with its headquarters in Pakistan and Afghanistan and its focus on the Afghan war. Aligned to the Deobandi school of thought, Heji emerged as the armed wing of the Jamiat-e-Ulemai Islam Pakistan, an organisation of Islamic clergy fighting the Soviet Union in Afghanistan.

Security agencies in Kashmir Valley believe it was involved in the Kashmir insurgency as early as 1989. However, its role was then limited to training Kashmiri youth. Around 1,000 Kashmiri militants were trained in various camps run by the outfit at Khoat, Afghanistan.

In 1985, the group split and Harkat-ul-Mojahedin (Hum) emerged as a splinter group of the pan-Islamic militant outfit Heji. It is understood that a senior leader of Heji, Maulana Fazlul Rehman Khalil, parted ways after problems cropped up between him and the Heji amir (chief) Qazi Saifullah over the launch of the Hum. Qazi was succeeded by Maulana Irshad Ahmad as Heji Amir but died fighting in Afghanistan in 1991.

Sources say that Maulana Shahadatullah took over as the Heji amir after the killing of Maulana Irshad in 1991. It is said that Shahadatullah wanted to reunite Hum with Heji so that "by combining the sources of finance, weapons and cadre, the outfit can operate effectively and make its presence felt".

Irshad sought the help of the clergy and following the efforts of Maulana Qaleemullah, chancellor of Darul-Uloom Jamia Farooqi, Karachi, Mufti Rasheed Ahmad, chancellor of Darul-Ifta-Wal-Irshad, Karachi and Maulana Rafi Usmani, also a senior clergyman.

The two factions finally agreed to merge as Harkat-ul-Ansar. The unification process took a few years and, according to police sources in Srinagar, Maulana Masood Azhar, general secretary of the unified outfit, was specially sent to implement the merger on the ground in Kashmir. The police claim Azhar sneaked into India on a Portuguese passport, identifying himself as Issa Wali Adam.

Azhar had flown from London to New Delhi via Bangladesh and entered Kashmir on February 9 1994. But he was arrested along with senior Harkat commander Sajjad Afghani at Khanabal in south Kashmir on April 13 1994 by the army.

Moulana Azhar Masood was later released in exchange for the crew and passengers of an Indian airliner which was hijacked to Kandahar in December 1999. Azhar is one among the 20 men India wants Pakistan to extradite after his group was blamed for the December 13 attack on Indian parliament and October 1 suicide attack on Kashmir assembly in Sringar.

Heji, however, came under severe pressure when it was declared a terrorist organisation by the United States in 1995 for the abduction of western tourists in Kashmir. And when Azhar came out of jail, he launched Jaish-e-mohammad group, although the majority of the men in his group were Heji activits.

Why would Heji attack the US consulate in India at this particular time? It is difficult to believe that it could actually strike in such a way in Calcutta because the group is not active even in Kashmir after Azhar carved out Jaishi-e-Mohammad from within its cadre.

But if they are involved, the action is almost certainly aimed at Gen Musharraf rather than India. Jihadi forces in Pakistan are under tremendous pressure from Gen Musharraf, who has been emboldened to severely curb their activities because of substantial public support.

The ban on Lashkar and Jaish earlier this month failed to provoke a single big protest, even in the jihadi strongholds inside Pakistan. The only way to divert Musharraf's attention would be through an Indo-Pakistani war.

Such a war would not only help the jihadi forces within Pakistan to get back to the centre stage of politics but also ease pressure on fleeing Taliban and Al-Qaida men from Afghanistan who are being prevented to enter Pakistani soil by the army.

· Muzamil Jaleel, a journalist with the Indian Express, is on attachment to Guardian Unlimited and the Observer